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1.
Heliyon ; 10(10): e31107, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38803851

RESUMO

The building sector is a major contributor to the world's energy consumption, exhibiting an ever-increasing trend. Heat losses through the building envelope constitute the most significant factor. Furthermore, the construction process has seen limited technological advancements in recent years, remaining heavily reliant on manual labor. Additive manufacturing emerges as a promising approach, with applications in the building sector on the rise. However, research on the thermal performance of 3D-printed components remains limited. Despite its recent introduction in the construction industry, 3D printing has yet to attain a level of maturity commensurate with other established methods. This paper aims to reduce this gap by analyzing 3D-printed blocks from a heat transfer perspective. The article introduces two key innovations. Firstly, it explores the design of various internal geometries and air gaps aimed at minimizing heat flux exchange between block surfaces. Secondly, it presents an experimental study conducted with a custom-designed setup tailored for testing 3D printed blocks. The blocks are constructed using recyclable plastic material and feature different internal geometries based on hexagonal cells. While the plan size of the cells remains consistent, their vertical structures vary as follows: 1) Block 1: Hexagonal air cavities without horizontal partitions. 2) Block 2: Hexagonal air cavities with three horizontal partitions, dividing the cells vertically into four parts. 3) Block 3: Honeycomb structure characterized by three horizontal partitions and staggering along the vertical axis. Their performance was experimentally evaluated using the Hot Box method, heat flow meter sensors, and infrared thermography. The results demonstrated reductions of up to 11.5 % in terms of thermal transmittance (U-value) with the inclusion of horizontal partitions. Starting from a U-value of 1.22 ± 0.04 W/m2K (Block 1), a transmittance of 1.08 ± 0.04 W/m2K was achieved for the honeycomb structure with horizontal partitions (Block 3).

2.
Sci Rep ; 11(1): 22482, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795373

RESUMO

Dual mode imaging in the mid infrared band, a joint use of thermography and quasi-thermal reflectography, was recently proposed as a full field diagnostic tool in cultural heritage. Here we discuss for the first time, to the best of our knowledge, a detailed application of such non destructive technique to the diagnostics of frescoes, with an emphasis on the location of detachments. We also investigate the use of a thermographic method based on TSR (thermal signal reconstruction), in a long pulse stimulus scheme, as well as the spatial registration of thermal images after post-processing analysis to their visible counterpart, so as to obtain a fine resolution diagnostic map. As an exemplar case study, we report about the application of dual mode imaging with a 500 [Formula: see text] pixel size at object plane on the "Monocromo", a fresco by Leonardo da Vinci located in the Sforza Castle (Milan, Italy). Our technique was used to guide the conservators during the restoration works, opening new perspectives in artwork diagnostics.

3.
Sci Rep ; 11(1): 273, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431985

RESUMO

The eye lens is a unique organ as no cells can be replaced throughout life. This makes it decisive that the lens is protected against damaging UV-radiation. An ultraviolet (UV)-absorbing compound of unknown identity is present in the aqueous humor of geese (wild and domestic) and other birds flying at high altitudes. A goose aqueous humor extract, that was believed to contain the UV protective compound which was designated as "compound X", was fractionated and examined using a variety of spectroscopic techniques including LC-MS and high field one- and two dimensional-NMR methods. A series of compounds were identified but none of them appeared to be the UV protective "compound X". It may be that the level of the UV protective compound in goose aqueous humor is much less than the compounds identified in our investigation, or it may have been degraded by the isolation and chromatographic purification protocols used in our investigations.


Assuntos
Aves , Olho/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Animais , Humor Aquoso/metabolismo , Ácido Ascórbico/metabolismo , Aves/metabolismo , Olho/metabolismo , Voo Animal
4.
Sensors (Basel) ; 20(4)2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32075259

RESUMO

The evaluation of photovoltaic (PV) system's efficiency loss, due to the onset of faults that reduce the output power, is crucial. The challenge is to speed up the evaluation of electric efficiency by coupling the electric characterization of panels with information gathered from module diagnosis, amongst which the most commonly employed technique is thermographic inspection. The aim of this work is to correlate panels' thermal images with their efficiency: a "thermal signature" of panels can be of help in identifying the fault typology and, moreover, for assessing efficiency loss. This allows to identify electrical power output losses without interrupting the PV system operation thanks to an advanced PV thermography characterization. In this paper, 12 faulted working panels were investigated. Their electrical models were implemented in MATLAB environment and developed to retrieve the ideal I-V characteristic (from ratings), the actual (operative) I-V characteristics and electric efficiency. Given the curves shape and relative difference, based on three reference points (namely, open circuit, short circuit, and maximum power points), faults' typology has been evidenced. Information gathered from infrared thermography imaging, simultaneously carried out on panels during operation, were matched with those from electrical characterization. Panels' "thermal signature" has been coupled with the "electrical signature", to obtain an overall depiction of panels' health status.

5.
J Imaging ; 6(8)2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34460691

RESUMO

Three-dimensional (3D) imaging and infrared (IR) thermography are powerful tools in many areas in engineering and sciences. Their joint use is of great interest in the buildings sector, allowing inspection and non-destructive testing of elements as well as an evaluation of the energy efficiency. When dealing with large and complex structures, as buildings (particularly historical) generally are, 3D thermography inspection is enhanced by Unmanned Aerial Vehicles (UAV-also known as drones). The aim of this paper is to propose a simple and cost-effective system for aerial 3D thermography of buildings. Special attention is thus payed to instrument and reconstruction software choice. After a very brief introduction to IR thermography for buildings and 3D thermography, the system is described. Some experimental results are given to validate the proposal.

6.
ACS Chem Neurosci ; 10(5): 2222-2228, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30609891

RESUMO

The effect of methoxy and hydroxy substitutions in different positions of the phenoxy moiety of the N-((6,6-diphenyl-1,4-dioxan-2-yl)methyl)-2-phenoxyethan-1-amine scaffold on the affinity/activity for D2-like, 5-HT1A, and α1-adrenoceptor subtypes was evaluated. Multitarget compounds with suitable combinations of dopaminergic and serotoninergic profiles were discovered. In particular, the 2-methoxy derivative 3 showed a multitarget combination of 5-HT1A/D4 agonism and D2/D3/5-HT2A antagonism, which may be a favorable profile for the treatment of schizophrenia. Interestingly, the 3-hydroxy derivative 8 behaved as a partial agonist at D2 and as a potent full agonist at D3 and D4 subtypes. In addition to its potent 5-HT1A receptor agonism, such a dopaminergic profile makes 8 a potential multitarget compound for the treatment of Parkinson's disease (PD). Indeed, the activation of 5-HT1A receptors might be helpful in reducing dyskinetic side effects associated with dopaminergic stimulation.


Assuntos
Antipsicóticos/uso terapêutico , Antagonistas dos Receptores de Dopamina D2/uso terapêutico , Receptores de Dopamina D4/agonistas , Esquizofrenia/tratamento farmacológico , Agonistas do Receptor 5-HT1 de Serotonina/uso terapêutico , Antagonistas do Receptor 5-HT2 de Serotonina/uso terapêutico , Animais , Antipsicóticos/farmacologia , Antagonistas dos Receptores de Dopamina D2/farmacologia , Descoberta de Drogas , Humanos , Agonistas do Receptor 5-HT1 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Relação Estrutura-Atividade
7.
J Imaging ; 5(6)2019 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34460498

RESUMO

The problem of deterioration of marble or stone monuments on display in the open air was raised in scientific terms around the mid-nineteenth century, correctly sensing the close dependence between the increased speed of surfaces alteration and air pollution. However, only more recently, around the years 1980-1990, emerged a need for quantitative data to assess the degree of degradation and the relative danger in the future projections. Non-destructive techniques can be an important aid in assessing the state of degradation and, above all, its speed, directly on the most important monuments exposed to the urban environment. In this work we discuss some non-destructive techniques able to evaluate the alteration of the surface shape of artefacts exposed to the environment through a non-contact survey of their surface shape. Advantages and disadvantages will be highlighted, as well as the problems still open.

8.
Pharmacol Res ; 111: 155-162, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27293049

RESUMO

Tumor homing peptides (THPs) specific for a representative breast cancer cell line (MCF-7) were carefully selected basing on a phage-displayed peptide library freely available on the web, namely the "TumorHoPe: A Database of Tumor Homing Peptides". The selected THPs were synthesized and evaluated in terms of their affinity toward MCF-7 cells. Out of 5 tested THPs, 3 best-performing peptide sequences and 1 scrambled sequence were separately conjugated to spherical gold nanoparticles yielding stable nanoconjugates. THP nanoconjugates were examined for their ability to actively target MCF-7 cells in comparison to noncancerous 3T3-L1 fibroblast cells. These THP-gold nanoconjugates exhibited good selectivity and binding affinity by flow cytometry, and low cytotoxicity as assayed by cell death experiments. The uptake of targeted nanoconjugates by the breast cancer cells was confirmed by transmission electron microscopy analysis. This work demonstrates that it is possible to exploit the conjugation of short peptides selected from phage-displayed libraries to develop nanomaterials reliably endowed with tumor targeting potential irrespective of a specific knowledge of the target cell biology.


Assuntos
Neoplasias da Mama/metabolismo , Técnicas de Visualização da Superfície Celular , Portadores de Fármacos , Ouro/química , Nanopartículas Metálicas , Nanoconjugados , Biblioteca de Peptídeos , Peptídeos/metabolismo , Células 3T3-L1 , Animais , Transporte Biológico , Neoplasias da Mama/genética , Neoplasias da Mama/ultraestrutura , Composição de Medicamentos , Feminino , Humanos , Células MCF-7 , Camundongos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Peptídeos/química
9.
Chem Biodivers ; 11(2): 197-208, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24591311

RESUMO

Receptor-subtype selectivity is an important issue in medicinal chemistry and can become very difficult to achieve if the actual binding pockets of the respective receptors are highly conserved. For such cases, known unselective ligands could be equipped with a spacer that sticks outside the actual orthosteric binding pocket towards the extracellular loops. The end of the spacer bears certain functional groups to enable specific or unspecific interactions with the receptor residues outside the binding cavity. Our experiments indicated that it is possible to achieve selectivity within the dopamine D1 family with such 'loop-hooks'.


Assuntos
Isoquinolinas/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Sítios de Ligação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Isoquinolinas/síntese química , Isoquinolinas/química , Ligantes , Estrutura Molecular , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Relação Estrutura-Atividade
10.
Molecules ; 18(9): 10747-67, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-24005968

RESUMO

Alzheimer's disease (AD) is characterized by irreversible and progressive loss of memory and cognition and profound neuronal loss. Current therapeutic strategies for the treatment of AD have been directed to a variety of targets with the aim of reversing or preventing the disease but, unfortunately, the available treatments often produce no significant clinical benefits. During the last decades compounds that inhibit or modulate γ-secretase, reducing ß amyloid (Aß) levels, have been considered as potential therapeutics for AD. Among these the (R)-enantiomer of flurbiprofen (FLU) seems to be very promising, but it shows low brain penetration. In this study, in order to improve the properties of FLU against Alzheimer's pathogenesis we synthesized some novel FLU lipophilic analogues. Lipophilicity of the new molecules has been characterized in terms of clogP, log K(C18/W) and log K(IAM/W) values. Permeability has been determined in both gastrointestinal PAMPA (PAMPA-GI) at different pH values and in brain blood barrier PAMPA (PAMPA-BBB) models. They were also tested for their ability to inhibit in vitro γ-secretase activity using rat CTXTNA2 astrocytes. Interestingly, the investigated molecules demonstrated to reduce Aß 42 levels without affecting the amyloid precursor protein APP level in a clear concentrations-dependent manner.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Anti-Inflamatórios não Esteroides/síntese química , Flurbiprofeno/análogos & derivados , Flurbiprofeno/síntese química , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Barreira Hematoencefálica , Linhagem Celular , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Flurbiprofeno/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Modelos Biológicos , Permeabilidade , Ratos , Estereoisomerismo
11.
Opt Express ; 20(13): 14746-53, 2012 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-22714535

RESUMO

In the artwork conservation field, non contact diagnostic and imaging methods are widely used and most welcomed. In this work a new imaging tool, called Thermal Quasi-Reflectography (TQR), is proposed and demonstrated. It is based on the recording, by suitable procedures, of reflected infrared radiation in the MWIR band (3-5 µm). The technique, simple to perform, can provide very interesting results in the analysis of the painting surfaces. TQR was demonstrated in situ on two famous artworks: the Zavattari's frescos in the Chapel of Theodelinda (Italy) and the masterpiece by Piero della Francesca "The Resurrection" (Italy).


Assuntos
Pintura/análise , Pinturas/classificação , Fotometria/instrumentação , Fotometria/métodos , Termografia/instrumentação , Termografia/métodos , Desenho de Equipamento , Análise de Falha de Equipamento
12.
Med Chem ; 8(4): 699-704, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22530895

RESUMO

Dopamine (DA) agonists, bearing catechol or phenol rings, are endowed with low oral bioavailability and short effect duration. In this report, the synthesis of novel differently substituted 4-(3-pyridyl)-1,2,3,4-tetrahydroisoquinolines and (1,2,3,4-tetrahydroisoquinolin-4-yl)phenylmethanols as potential non phenolic and non catecholic DA receptor ligands is reported. The new compounds, evaluated by binding tests on cerebral striatal membranes, bound to DA receptors with moderate affinity. Anyhow, they may represent a starting point to develop new DA ligands endowed with better pharmacokinetic and metabolic properties.


Assuntos
Ligantes , Sondas Moleculares/síntese química , Receptores Dopaminérgicos/metabolismo , Tetra-Hidroisoquinolinas/síntese química , Sítios de Ligação , Estrutura Molecular , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/química
13.
Bioorg Med Chem ; 18(19): 7085-91, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20801048

RESUMO

Based on the well known biological versatility of the imidazoline nucleus, we prepared the novel derivatives 3a-k inspired by 2-BFI scaffold to assess imidazoline molecules as D(2)-like dopamine receptor ligands. Conservative chemical modifications of the lead structure, such as the introduction of an hydroxy group in the aromatic ring alone or associated with N-benzyl substitution, provided partial (3f) or nearly full (3e and 3h) agonists, all endowed with D(2)-like potency comparable to that of dopamine.


Assuntos
Benzofuranos/farmacologia , Imidazóis/farmacologia , Receptores de Dopamina D2/agonistas , Animais , Benzofuranos/síntese química , Benzofuranos/química , Sítios de Ligação , Imidazóis/síntese química , Imidazóis/química , Ligantes , Masculino , Modelos Moleculares , Estrutura Molecular , Ratos , Ratos Wistar , Estereoisomerismo , Relação Estrutura-Atividade
14.
Future Med Chem ; 2(8): 1247-52, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21426016

RESUMO

The series of Camerino Symposia present the most recent knowledge and discoveries in the growing field of drug-receptor interactions and the design and mechanisms of drug action. Lead discovery, G protein-coupled receptors (GPCRs) and polypharmacology were the general subjects covered in this Tripartite European Meeting in Medicinal Chemistry chaired by Mario Giannella (University of Camerino, Italy). Specifically, the meeting focused on the selection criteria and application of computational methods and stem cell technology in/to lead discovery, as well as providing an update on targeting GPCRs. In addition, the importance of polypharmacology in drug discovery for many GPCRs was widely highlighted. Approximately 110 participants in an international audience composed principally of chemists, biochemists and pharmacologists spent the 5 days of the conference in the eye-catching medieval setting of the University of Camerino and enjoyed both the scientific and cultural programs.


Assuntos
Descoberta de Drogas , Receptores Acoplados a Proteínas G/química , Animais , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Ligantes , Neuropeptídeos/antagonistas & inibidores , Orexinas , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/metabolismo , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Células-Tronco/efeitos dos fármacos
15.
IEEE Trans Image Process ; 13(3): 390-6, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15376930

RESUMO

A new optoelectronic system based on a projection unit in which light, coming from a laser diode coupled to an optic fiber impinges on a diffractive optical element (DOE) to produce sinusoidal fringes is proposed for three-dimensional (3-D) texture measurement. If the projected fringe pattern is viewed at an angle different from the projection angle, the fringe profile is phase-modulated by the 3-D object shape. The 3-D map information is obtained with the aid of a fringe analyzer based on phase-shifting synthetic moiré pattern, Fast Fourier Transform (FFT), signal demodulation techniques and a robust and fast phase unwrapping performed by a specially developed software. The proposed system is based on a simple and low cost equipment; furthermore, it is suitable for in situ measurements also by nonskilled operators. Some experimental examples illustrate its performance.


Assuntos
Arqueologia/instrumentação , Arte , Tecnologia de Fibra Óptica/instrumentação , Interpretação de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Armazenamento e Recuperação da Informação/métodos , Processamento de Sinais Assistido por Computador/instrumentação , Algoritmos , Antropologia Cultural/instrumentação , Antropologia Cultural/métodos , Arqueologia/métodos , Arquivos , Eletrônica , Desenho de Equipamento , Análise de Falha de Equipamento , Tecnologia de Fibra Óptica/métodos , Aumento da Imagem/instrumentação , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Modelos Estatísticos , Reconhecimento Automatizado de Padrão , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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